Hydraulic log debarker



July 23, 1957 Y L. R. FOREMAN HYDRAULIC L0G DEBARKER' 4 Shets-Sheet l Filed March 19. 1956 I INVENTOR LEMUEL R. FOREMAN BY Swim/2&5 &

ATTORNEYS L. R. FOREMAN HYDRAULIC LOG DEBARKER July 23, 1957 '4 Sheets-Sheet 2 Filed March 19, 1956 mm F R. L m E. L

ATTORNEYS ,1957 i V L. R. FOREMAN 2,800,155

; v HYDRAULIC LOG DEBARKER Filed March 19. 1956 4 Sheets-Sheet 5 INVEN'i'OR LEMUEL R. FOREMAN ATTORNEYS y 1957 I L. R. FOREMAN 2,800,155

' HYDRAULIC LOG DEBARKER Filed March 19, 1956 4 Sheets-Sheet 4 llllll lllllillllll lllllllllllll 'lllllllllillllllllllllllllllllllH!!\|l|ll'lllllll|l\llll llllllll\l\l INVENTOR LEMUEL R. FOREMA/V BY 5172mm! & 5117mm;

ATTORNEYS HYDRAULIC LOG DEBARKER Lemuel R. Foreman, Elizabeth City, N. C. Application March 19,1956, Serial No. 572,572 1 Claim. (Cl. 144- 208) The present invention relates to the debarking of logs and more particularly to a process and apparatus for bark removal in which a stream of water projected at high velocities is employed as the primary debarking instrumentality. V i

The hydraulic debarking of logs has been practiced for some time and there are presently available numerous types of apparatus in which one or more jets of water are utilized to free the bark layer from logs. In many instances, however, it is necessary to precede and/or. supplement this hydraulic action by a mechanical disintegration or at least partial separation of the bark because of limitations in the effectiveness of the hydraulic cleaning.

A principal object of the present invention is'to provide an improved method of log debarking entailing only the use of a single water jet under conditions enabling superior operating economies and efiiciencies.

A second object of my invention is to provide a hydraulic debarker in which mechanical simplification materially reduces maintenance as well as operating problems and personnel.

Another object of my invention is to provide a hydraulic debarker applicable to the handling of logs of mill run varieties without a preliminary classification thereof.

A further object of my invention is to provide a hydraulic debarker capable of the processing or cleaning of logs of diverse sizes both as to length and as to caliper.

A further object of the invention is vto provide a hydraulic log debarker capable of processing successively logs with a constantly high overall rate of output.

Other objects and advantages of the, invention will be readily apparent from the following detailed description of a preferred embodiment thereof when taken in conjunction with the accompanying drawings wherein:

Fig. 1 is an end elevation of apparatus embodying the principles of my invention;

Fig. 2 is a plan view thereof;

Fig. 3 is a front elevation of the log support and its carriage;

Fig. 4 is a schematic showing of the propulsion mechanism connected with the log support;

Fig. 5 is a vertical cross section of the log support as taken substantially along the line 55 of Fig. 3, certain parts being broken away, certain parts being omitted, and certain parts being shown in phantom outline;

Fig. 6 is a vertical cross section of the log support taken substantially along the line 6-6 of Fig. 3;

Fig. 7 is a fragmentary end elevation showing in detail the manner of water nozzle support in the apparatus;

Fig. 8 is a detail front elevation of the nozzle support of Fig. 7;

Fig. 9 is a horizontal cross section that has been rotated 90 degrees clockwise from the position indicated by the line 99 of Fig. 8;

Fig. 10 is a vertical longitudnial section of the water nozzle per se taken along the line 10-10 of Fig. 7;

Fig. 11 is a vertical cross section of the nozzle taken substantially along the line 11-11 of Fig. 10; and

Patented July 23, 1957 2 Fig. 124s a bottom plan view of the nozzle-plate as sembly. 1 In general, thepresent invention contemplates the hydraulicdebarkingof, a succession of logs serially advanced while" undergoing rotation about their longitudinal axes to pass beneatha-fi xed, substantially flat, fan-like jet of high velocity. water,-the plane of whichparallels the lineof travel of said logs.

Referring to the drawings, the debarking apparatus includes a log deck 1 of conventional skeletal construction adapted to receive and hold a supply of logs 2 preliminary to the debarking thereof. From the log deck, a chain conveyor or comparable log haul with which is combined a-conventional indexing log-release mechanism serves to feeda succession of individual logs along a sloped ramp section 3 for placement'upon a supporting carriage 5 which transports each log beneath the hydraulic debarker. This; functioning of a live log deck is well known in thelumberin-dustry and since it is only an incidental element ofthe present-invention requires no further elaboration. Equivalent means for loading logs upon the carriage 5 would serve equally as well.

The carriage 5 includes a plurality of spaced pairs of corrugated wheels 6 secured in linearly matched relation along parallel shafts 7 and 8, journalled in suitable bearing s 10 placed at intervals along the shafts, said bearings being secured to I-beams 11 disposed transversely of a conveyor car 14. The shafts 7 and 8 are so spaced that the opposed pairs of wheels 6 provide a cradle into which one of the logs 2 may-be deposited from the log deck 1 and in which it will be retained during the debarking operation. The wheels 6 are corrugated or otherwise surfaced asdesiredto enable good frictional driving engagement with the logs carried thereby while minimizing mechanical deterioration or impairment of the log bodies.

A gear 16secured to one end of the shaft 7 meshes with a drive gear '17 attached to the stub shaft of a geared electric motor 19 mounted upon the carriage 14. The niotor 19 is connected through an overhead cable 20 to a suitable source of direct current and is controlled from aremote operating station (not shown) to rotate the shaft 7 as desired. By means of matching sprocket wheels 25, secured to the shafts 7 and 8 and interconnected by' a chain 26, the shafts are rotated in unison, moving the wheels 6 in the samedirection to rotate the log 2 cradled therebetween. Initial rotation of the log upon the supporting wheels is accompanied by an automatic alinement thereof in the cradle, compensating for surface irregularities, thus permitting a subsequent steady and continuous rotation throughout the full debarking operation.

The conveyor car 14 upon which is supported the log carriage 5 is formed of a pair of side frame members 30 united and maintained in spaced parallel alinement by the transverse I-beams 11 mounted thereon, with terminal bars 31completing the bed frame of the car. Matching pairs 33 of bearing blocks are disposed at suitable intervals along the side frame members 30 and carry axles 34 upon the ends of which are secured flanged wheels 35. The wheels 35 of the car 14 ride upon track elements 36 attached to the base flanges 37 of opposed members 38, substantially C-shaped in cross section, maintained in spaced parallel relation upon a suitable supporting structure and having a floor plate 40 extending therebetween.

The conveyor car 14 is provided with a shielding cover 42 of peaked metal plate sections enclosing the areas between the spaced transverse beams 11 and extending to each side of the car 14 a distance sufiicient to cover the track supporting elements 38. Dependent flanges 43 project from the cover 42 to a point below the upper edges of the elements 38 to provide a splash shield therefor. A

cover 46 encloses the motor 19 and includes a vertical splash shield 47 extending upwardly therefrom.

The conveyor car 14 is reciprocated over the tracks 36 by means of control cables 50 and 51 attached to coupling bars 52 dependent from the body frame of the car. The cable 50 extends directly to and is wound about one end of a double drum 53 actuated by a reversible direct current motor and gear reducer (not shown). The cable 51 extends forwardly of the car 14, passes around aguide pulley 55 and then returns to the opposite end of the double drum 53. Rotation of the drum 53 will move the car steadily and at any desired speed over the tracks, controls for the drive motor being located at the remote station from which operation thereof is directed. Suitable safety cut-off switches are preferably connected in the control circuit to limit movement of the car 14. For example, a trip lever 58 is mounted upon a suitable bracket 59 extending from the leading edge of thecar 14 to open a switch (not shown) halting forward travel of the car after it passes a predetermined location. Similarly, engagement of the rear edge of the car 14 with a trip switch (not shown), suitably located, adjacent the limit of reverse travel of the car will interrupt such reverse travel in the event the operator fails to shut off the power. A pneumatic cushioning bumper 60 is also included at the end of reverse travel of the car 14 to assist in proper positioning of the car at the log-loading station.

As best shown in Fig. 5, troughs or gutters are positioned along each side of the car track, conveniently being secured to the track supporting beams 38, and are sloped downwardly toward the front of the track to carry used water and bark fragments separated from the logs undergoing treatment away from the apparatus. An endless conveyor belt or chain 71 is disposed for movement along and within each of the troughs 70 to assist in the advance of waste material along the troughs. A suitable depot for collecting, screening and/ or classifying of the waste products including the necessary handling and transfer equipment is provided at the end of the apparatus. A plate scraper 74 having side lugs 74a extending over the tracks 36 is suspended from the leading edge of the car 14, as by means of strap hinges 75 dependent from the forward cross member 31, and serves to clean away any debris falling between the track elements 38, pushing it along the tracks 36 and the floor 40 into the common collection system as the car 14 is advanced, thus maintaining the travel area free of obstruction.

An elevated bridge is supported above and transversely across the line-of travel of the car 14 at a point slightly in advance of the log deck 1 and loading station upon vertical members 81 which conveniently may be in the form of I-beams united in spaced parallel relation by means of bracing elements 82. Plates 84 secured to and projecting outwardly from the supports 81 at the upper extremities thereof provide rail sections over which the vertically reciprocal movement of a horizontally disposed water head 85, extending therebetween, is enabled. The header 85 is supported in mounting blocks 86 secured to the inner surface of nested angle irons 87 so arranged and united as to form a slot 88 fitting over and sliding upon the projecting portion of the plate 84. Racks 90 are attached to the outer edges of the nested irons 87, projecting vertically to each side thereof so as to lie in spaced parallel relation to the guide plates 84. Pinion gears 92 secured to a shaft 93 journalled in the upright supports 81 engage each of the racks 90 and effect movement thereof upon rotation of the shaft 93 by a reversible, geared electric motor 94 mounted upon a shelf 95 provided at one side of the bridge 80. Controls for the motor 94 are located with the other controls atthe central station from which the apparatus is directed. A rack secured to the water header 85 intermediate the ends thereof engages and is driven by a pinion gear 101 of a motor drive unit 103 dependent from an adjacent cross member 104 extending between the angles 87 in parallel alinement with the header 85. The motor drive 103 is also under the control of the operator of the apparatus at the remote station and enables a transverse reciprocation of the header 85 when necessary while the apparatus remains in operation.

The water header 85 is located at one end and at the other end is connected by a flexible hose 108 to a line 109 supplied with water from a convenient source. Booster pumps 110 connected in series in the line 109 insure a water pressure of 1400 pounds per square inch gauge and have a capacity of at least 700 gallons per minute. It is preferred that the flexible hose 108 include a compensating loop 108a with a minimum of a 10 foot radius to enable ready adjustment of the header 85 while eliminating excessive strain on the hose per se as well as its auxiliary couplings.

The water header 85 is provided with a downwardly directed orifice, intermediate its ends over which a nozzle 116 is secured. Through this nozzle 116, a jet 117 of high pressure water may be created for the actual debarking operation. The nozzle 116 includes a sleeve 120 adapted for placement around the header 85, said sleeve having an internal orifice 121 which is in register with the orifice 115. The base of the sleeve 120 terminates in shoulders 125 from which project wings 126 carrying dependent flanges 127 peripherally recessed to receive closure plates 128 positioned by means of stud bolts 129. The meeting faces of flanges 127 and plates 128 are machined to enable the formation of a direct metal to metal water tight joint, while the abutting edges of the plates 128 are angularly ground through the major portion of their lengths, and the plates are so positioned that the tapering sides define a narrow slot 130, approximately of an inch in width at its outer surface. The slot 130 expands inwardly and opens into an interior chamber 131 which communicates with the orifice 121, from which water is supplied under pressure to generate the jet 117 in a flattened, fan-shape form. Erosive action of the high-pressure Water forced through the slot 130 causes a gradual increase in the Width thereof. T o avoid excessive replacement costs, the regrinding of the abutting edges of the plates 128 is contemplated, take-up screws 132 being positioned in one of the flanges 127 along the outer edge thereof to enable proper placement of the reground plates, additional shimming elements being employed as needed.

The nozzle 116 for best operation is placed approximately 24 inches from the surface of the log 2 to be debarked, with the jet-generating slot 130 in parallel alinement with the log axis but slightly off center with respect thereto. Nozzle placement and adjustment for logs of varying caliper (as shown diagrammatically in Fig. 7) is readily accomplished upon initiation of the debarking operation, by manipulation of the several controls which have already been described. The water jet when properly directed peels the bark layer from the log and simultaneously effects a distintegration of the removed bark to simplify subsequent handling thereof.

After the debarking of a log has been completed, its removal from the supporting wheels 6 is expedited by an unloader mechanism disposed in advance of the bridge structure 80. The unloader device includes a plurality of spaced kicker arms pivotally mounted at one end thereof upon a suitable frame work disposed above the track elements 38 adjacent their forward ends. The kicker arms 140 extend downwardly a distance sufiicient to extend below the base of any log cradled between the supporting wheels 6 and are so spaced that upon arcuate movement thereof, the arms 140 will pass between said supporting wheels, clearing, of course, the shaft 8 carrying the wheels. Steam rams 141 control the movement of the arms 140 and advance them from a positionbeside the log support 5 forwardly into engagement with the log 2 lifting it from between the wheels 6 and olfcf the car 14.. This log removal may be'assisted by reversing the direction of rotation of the wheels 6. The logs drop on guide bars 143 and are discharged into an adjacent trough 144 through which an endless conveyor 145 will transport them to the saw mill, storage dock or other disposal point. The car 14 is withdrawn from the unloading station and returned to its original starting position where it will receive another log for processing. As soon as the way is clear, the rams 141 are retracted to return the arms 140 to their place along side the tracks 36 in readiness for the next unloading operation.

The debarking operation, as will have become apparent from the foregoing description is relatively simple. The conveyor car 14 is indexed in front of the ramp 3 and a single log is released from the deck 1 to move into position upon the car, the log falling between the pairs of supporting wheels 6, which are being rotated. The iog 2 is cradled between the wheels 6 and by frictional engagement therewith is caused to rotate in a reverse direction, that is counter-clockwise as shown in Fig. 5. The initial revolutions of the log upon the supporting wheels 6 will establish its linearly balanced position upon the carriage 5 as the car 14 is started to advance along the tracks 36 to pass beneath the water jet 117. As the leading edge of the log enters the stream of water, adjustment of the nozzle position (as shown in Fig. 7) may be effected for maximum efficiency in the debarking operation. Placement of the line of jet impact to one side of the longitudinal axis of the log enables the flow of water to peel the bark therefrom rather than to drive the bark into the body of the log. With the remote control station being so located that the operator can observe the debarking operation, manipulation of the various portions of the apparatus is quite easy. The car 14 is moved forwardly under the water jet and its movement correlated with the speed of rotation of the log supported thereon to enable complete debarking. The car 14 is then advanced until it clears the bridge structure 80. Rotation of the supporting wheels 6 is reversed and the kicker arms 140 are brought into contact with the log 2 to lift and to discharge it from the car 14, a reversed rotation of the wheels 6 assisting in this operation. The car 14 is returned to its position in front of the loading deck and a new log is positioned thereon for the next debarking operation, while the arms 140 are retracted in readiness for the next unloading cycle.

Since the water jet 117 is arranged for angular impingement against an upwardly moving layer of bark, removal of the bark is more eflicient. Ready nozzle adjustment permits maintenance of highest debarking action and permits the operator to compensate for irregularities in log configurations during processing thereof. It has been observed that the action of the planar water jet is concentrated on the bark and its disintegration. As a result, any sand, grit or similar foreign matter entrapped in the bark during the logging operations is released therefrom and is carried away from the body of the log instead of being driven into it. Separation of this sand and grid from the bark admits simplified classification of the waste products and production of a clean bark which can be used for fuel without fear of grate or furnace deterioration through accumulated silica deposits. Additionally, the rapid debarking possible by my method and apparatus prevents the separated bark from being saturated with water, a condition which precludes bark utilization as fuel or disposition by burning.

The apparatus as contemplated by my invention enables a single operator to handle logs totaling from 12 to 15 thousand board feet per hour with a minimum of eiiort. The surfaces of the debarked logs are clean so that slabcuts and waste trim obtained from such logs are readily accepted by paper'mills. The apparatus is adapted to handle mill-run logs of various lengths, caliper and varieties without preclassification or grading thereof. The supporting wheels 6 are so spaced as to cradle without dilficulty logs varying in diameter from 4 to 54 inches. The car 14 is of a size sufiicient to handle logs of lengths up to 20 feet and, of course, longer logs could be accommodated simply by increasing the carriage size.

It'will be obvious that various modifications in the component parts of my apparatus, their form and arrangement, are possible without departing from the function of the invention or the scope of the appended claim.

I claim:

Apparatus for the debarking of logs comprising a log support including a series of spaced pairs of wheels disposed to form a cradle for a log, means for driving said supporting wheels to effect a rotation of such a cradled log about its horizontal axis, a water nozzle, means for mounting said nozzle above and in spaced parallel relation to said log support and to the central axis thereof, said nozzle-mounting means including means to move said nozzle vertically and laterally with respect to said central axis of said log support, means for longitudinally mov- I ing said log support beneath said nozzle, means for projecting a high-velocity and high-volume stream of Water substantially in fan-shape from said nozzle angularly of a peripheral surface of such log and in opposition to its axial rotation to peel bark therefrom during its movement beneath said nozzle.

References Cited in the file of this patent UNITED STATES PATENTS 1,300,748 Lombard Apr. 15, 1919 1,969,914 Swigert Aug. 14, 1934 2,396,255 Edwards et a1. Mar. 12, 1946 2,587,473 Holveck et al. Feb. 26, 1952 2,605,794 Guettler Aug. 5, 1952 2,652,867 Boswell Sept. 22, 1953 

